In the 18th century, Lord Fartsworth, was a lucrative apple salesman, selling apples to traveling circus' and carnies mainly for the purpose of apple bobbing. Having lots of cash he deviated into science and invented aviation, before the wright brothers. Due to coal not being invented yet, crafty Fartsworth used fermented apple juice to power flying machine that could travel 8000 small peasants in a single flight, but due to the apple fuel (chemical name AnuS-2-0), not being as volatile as desired, caused the engines to miss fire and make a strange sound as the excess gas escaped, this sound was rather prominent on Fartsworth 'Flying Fart Flapper' that flew to Alaska on auto pilot in 1732. Later on the sound was compared to the noise as gas escapes an anus, and got dubbed 'farting' in honor of lord Fartsworth.

Who would have thunk it?

(scene 18th century manor house in middle England, mid afternoon, some posh toff is having crumpets and tea)

Lady Jelly-Anus : Butler, is that the 17:05 from Oglethorpe i hear arriving? Lord Fartsworth is a fine aviator
Butler : No ma'am, i had a wicked fresh curry for breakfast, my arsehole feels like ive shit brown fire and now im farting as much as i can to cool it off.
Lady Jelly-Anus : My word, that must be frightfully fierce.
Butler : Look out here comes round 2.